Air/ Oil Cooled Servo Controlled Voltage Stabilizer has high and low voltage input cut off, over load and over temperature protection and wide input voltage operation. The Stabilizer has built in spike suppressor, more than 98% efficiency on full load and multifunction digital display. The Stabilizer comes with built in surge protection and ELCB protection. The Stabilizer has ambient temperature ranging from 0 ° c to 45 ° c and has input frequency ranging from 47 hz to 53 hz. The Stabilizer has correction rate of more than 100 v sec up to 15 KVA and 35v/ and has synchronous ac motor servo drive. The Air/ Oil Cooled Servo Controlled Voltage Stabilizer has capacity ranging from1 to 500 KVA and input voltage ranging from 170 V to 485 V.